SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'aa2e3f266376aa5226f13fcf3a0b58f4c99194c8b46bbf81dac7663c6cb91fba' 
  AND token = 'YKblS2OkaiLRJ+V6ZN7Vd4HLN9PE4YFn1aVaYAhenjo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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