SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2affd17bde9968ef7c560bfcd04768ef64bf19d2cec3a7456b2c3cbc7849c20e' 
  AND token = 'Lsb3Fwv/DyJrCRXH35sYZ44ahUIwL+AieuAsHBZ4bzY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}