SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'be5890e35a4b299250856896e143649ca8f0650cdb3d4c11edb24035a2b0632a' 
  AND token = 'aTIxrjz1L4M6zZQ7Ips6h9dsyBzbze3ZlHO61RH3xsA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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