SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7e328ec1195aabe5743e39ffdef8a027c3ad5aea86f4dbcb1241a2efc6da776b' 
  AND token = 'A07tx7N6iRpwyBFqJn1UxrjXxF0/6JdxqkPYdwPtBa4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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