SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '58eba1d507790303c25bb9f9efa9fc7a28dee92cd8347db9185e5c2a57cfd14d' 
  AND token = 'GmPqkCgeoS6v8evpphuLdM+kBzw9xiI3SXg7V0p5JXU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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