SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '8639c0416b3c8feb94e91190e8569c57b4e457e6b44f38de966f08657813fc0e' 
  AND token = 'ERsHssNAtXH/RE4kTIAdgslW0meVtwfPF2R2O+hqMS8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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