SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7895d42806b7bada55f73aec0dd7bab2865c5764aa08b07b593f71f0b138d38d' 
  AND token = 'lwRE4qWJd7hv5YbXPUPJB+N1DMMDm4ICZitvdVVY/Gg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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