SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '19cf72d69831433783e9b6d4c55098e469305b28b0ef78db3a11b0996222766b' 
  AND token = 'oZAK6FpUkSNzpawG18PUtQhWsoBnDiRhp6zerDvE4yM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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