SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'b4eeb82968c50ba9472dd870d22d72a0daa8f5111e25455d98b76a2360a0228a' 
  AND token = '1AxFAvlYV2fi39z4dFx94MOnL0wofCW9gAEc+iD59Lo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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