SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ee61473e24abd41a918b8bd50219118a698542c5dd582a8d46080f00e51ede17' 
  AND token = '7PPlMDKW+3+OmLKp3ThXl3/kWBSTJH0j4Fc7sXVMiPI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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