SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'e0eece29cc33b6ddf40220be51adde25653871f089c19394f180c6debf17a318' 
  AND token = 'locPfCGhapAs4VsfkSKTETRZic8dEiDVZxz27bpUQDE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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