SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0e38a5d4f5eb1481040d3aebc0eca9b3b14ef49c46c0b62338a009b035627440' 
  AND token = 'V03vWBwVaqx2C1CMLV8O/s4v3KFWa/vWRGRkuQdltIY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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