SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6bb346c261c430017349c1fa1155d907772584f3fe59fcf873c708486674450e' 
  AND token = 'W2PuJSLdqMJ7GtXRHWJHXTUhOzmf9T/H2EZe0zVMgGA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00062

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}