SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5144e0a1f311d7846b474fff06526fbcea46bc16498e386583713b1b73e3c0e3' 
  AND token = 'qj+Al/GpIoE8VzaF8va6BCimqMs8JGnVYBaFjZCEOtg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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