SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'f402fa6b69eb856813174a84ceb325e7a813c30ac97dba910c8f51d1fff131cd' 
  AND token = 'B/rEnWsHRYXhpF/A8IVshVHe773e3yeR8kL/PHj6lC4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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