SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '62f77ca2581664e1296b3175807af0364dd0468356ababadfcbd1334d8c6f5d7' 
  AND token = 'rBqpMcG8i9x/53ETiO6eUmc6fiJ3fyIVJHfkUT0oqi8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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